TY - JOUR ID - 56889 TI - Fine Sediment Input and Benthic Fauna Interactions at the Confluence of Two Large Rivers JO - International Journal of Environmental Research JA - IJER LA - en SN - 1735-6865 AU - Blettler, M. C. M. AU - Amsler, M. L. AU - Ezcurra de Drago, I. AU - Drago, E. AU - Paira, A. AU - Espinola, L. A. AU - Eberle, E. AU - Szupiany, R. AD - Ciudad Universitaria, Argentina Y1 - 2016 PY - 2016 VL - 10 IS - 1 SP - 65 EP - 76 KW - benthic invertebrate KW - Fine sediment load KW - Channel confluence KW - Large river KW - Sedimentology DO - 10.22059/ijer.2016.56889 N2 - Several studies suggest that invertebrate abundance and richness are disrupted and reset at confluences. Thus, junctions contribute disproportionately to the overall aquatic biodiversity of the river. In general terms, authors have reported high abundance and diversity due to the major physical heterogeneity at junctions. However, data are still scarce and uncertainties are plentiful.The impact of a great input of fine sediments on the distribution patterns of benthic invertebrates at a river confluence was quantitatively analyzed herein. The junction of the subtropical Bermejo River (high suspended sediment load) with the large Paraguay River is the selected study area to achieve this aim.While diversity increased slightly downstream the junction (from 0.21 to 0.36), density and richness of the macroinvertebrate assemblage significantly diminished downstream the confluence (from 29050 to 410 ind/m2; p< 0.05) due to the input of fine sediment from the Bermejo River (mean fine sediment increased downstream from 6.3 to 10.2 mg/L), causing a negatively impact on invertebrate assemblage. This study highlights the ecological importance of the sediment input effects on benthic invertebrates, a topic still poorly explored in river ecology.It is speculated that the spatial extent of the impact would be dependent upon the hydrological and sedimentological context, highly unequal between both rivers. New hypotheses should be tested through new studies considering different hydrological stages. UR - https://ijer.ut.ac.ir/article_56889.html L1 - https://ijer.ut.ac.ir/article_56889_9c839ce4b94eeb27cc3abdd951a98e9c.pdf ER -